If you are dealing with summer heat in a non-air-conditioned space or spending time outside this week, Sony’s fanless neck cooler is the most credible option on the market right now. At $260, it is not cheap, but it is significantly better than strapping a fan to your collar.
My wife has a bunch of the inexpensive fans for her neck. She uses them regularly. She also has a product I reviewed (the TORRAS COOLIFY 2S Neck Air Conditioner), which is similar in concept to the Sony Neck Cooler. There are metal plates that provide direct-contact cooling to the neck (and in the winter, they provide heat as well, so this product is good year-round).
The Sony version also has heating. What is interesting about it is the fact that it goes down the back of your neck, so it looks a bit more “concealed” than the TORRAS that I reviewed (which looks more like a spaceship around your neck). Same idea, and definitely something to help reduce the heat, which seems to be needed this summer!